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Questions & Answers
Does this include a glock mos plate? Manufacturer Answer

It does indeed!

by Vortex, Manufacturer, July 29, 2025
Will this fit the FN 509-C Tactical? Expert Answer

The Vortex Defender-ST is compatible with the FN 509 Compact Tactical. You will need to use the FN #501 MRD plate (Deltapoint Pro) that can be purchased directly from FN. With that plate installed, you will be able to install this optic.

by Ethan, Gear Expert, January 14, 2026
Customer Reviews
Helpful Positive Review
I put this sight on my Sig p320 x5 Legion and it connected direct without the need for a plate which i liked. The red dot is fine and clear (i got the 3MOA), and the glass is super clear with only a very slight blue tint to the glass. those were the ...
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2/2 found this helpful
Helpful Positive Review
it's okay i guess by panzos, Verified Owner, March 6, 2024
Well it's okay I guess it works this the product itself is nothing wrong with it it's not defective it works well I put it on my gun for a week I tried it this is just a personal preference I don't like it I don't like it because I don't like the way...
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8/127 found this helpful
Helpful Positive Review
Long story somewhat short, I have tried many, many red dots in the past couple of years. Trying the Likes of Swamp Fox, Vortex (Viper/Venom), SIG, , Trijicon, and Holosun. From my personal experience as well as vast amounts of research on how well ea...
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6/7 found this helpful
Helpful Positive Review
Great optic/Great warranty by Curt, Verified Owner, March 6, 2025
I mounted this on a Ruger RXM replacing a Romeo Zero that didn't have enough elevation adjustment. It barely co-witnesses with the irons, but I really like the size of the window and the shock shield over the body. Adjustments are easy to access and ...
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2/2 found this helpful
Helpful Positive Review
DEFENDER ST by danmic, Verified Owner, September 2, 2025
THIS IS ONE OF OUR FAVORITE RED DOTS, DOES THE JOB FOR WHAT WE WANT. LOVE THE PRICE AND THE WARRENTY. WE OWN SEVERAL VORTEX PRODUCTS. THE ONLY TIME WE HAD A PROBLEM, CALLED AND THEY SENT OUT A NEW ONE W A LABEL TO SEND THE OTHER BACK, NO PROBLEMS A...
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1/1 found this helpful
Helpful Positive Review
great improvement by TTF, Verified Owner, November 6, 2025
I had originally purchased the c.C.W version of this object, when they first came out, and I can tell you that the s t is far from that opinion, this big brother to that optic is phenomenal clear.Dot picture and it does not leg.And have dot cut off a...
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1/1 found this helpful
Read All 79 Reviews
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Product Info for Vortex Defender-ST 1x23mm Reflex Red Dot Sight

The Do-It-All Micro Red Dot. Handguns. Shotguns. Offset on a carbine. Whether running drills at the range or holding the line during rigorous duty use, the Defender-ST is ready when and wherever you are. Rugged and reliable? Its a given. Large sight window? Absolutely. Motion-activation and a dot with adjustable brightness deliver superior target acquisition, adaptability in all lighting conditions, and faster follow-up shots. Experience what shooters mean when they discuss the ideal, all-round red dot. With the Defender-ST, you're not just range-ready, but armored for the toughness and adaptability your world demands.image

Specifications for Vortex Defender-ST 1x23mm Reflex Red Dot Sight:

Manufacturer: Vortex
Magnification: 1 x
Objective Lens Diameter: 23 mm
Illumination Type: LED
Illumination Color: Red
Eye Relief: Unlimited
Adjustment Type: MOA
Emitter Type: Open
Battery Type: Lithium Metal, CR2032
Fogproof: Yes
Length: 2.03 in
Lens Finish: Fully Multi-Coated
Quantity: 1
Red Dot Sights-Footprint: Deltapoint Pro

Features of Vortex Defender-ST 1x23mm Reflex Red Dot Sight

  • Large hard coated aspherical lens, motion activation with 10 minute auto-shutoff
  • Shockshield Polymer Insert
  • Deltapoint Pro Footprint
  • Fast-Rack Texturing
  • Fully Multi-Coated Lenses
  • Armortek
  • Waterproof
  • Shockproof

Package Contents:

  • Vortex Defender-ST 1x23mm Reflex Red Dot Sight
  • Picatinny Mount
  • Custom Tool
  • Most Common Mounting Screw Sets
  • Lens Cloth
  • CR2032 Battery
  • Rubber Cover
  • Glock MOS Plate

Vortex Defender-ST 1x23mm Reflex Red Dot Sight Orderable Models

List of Orderable Models

  • Vortex Optics OPMOD Defender-ST 1x Reflex Micro Red Dot, 6 MOA Dot, Tan, 843829145855 , MPN: DFST-MRD6-OP-KIT2023 , UPC: 4292050 , Code: VX-RD-VOR0116-DFST-MRD6-OP-KIT2023
  • Vortex Defender-ST 1x23mm Micro Reflex Red Dot Sight, 3 MOA, Tan, DFST-MRD3-T , MPN: DFST-MRD3-T , UPC: 843829145831 , Code: VX-RD-VOR0116-DFST-MRD3-T
  • Vortex Defender-ST 3 MOA Red Dot Sight, Black, 1.8in, 1.48oz, DFST-MRD3 , MPN: DFST-MRD3 , UPC: 843829133296 , Code: VX-RD-VOR0116-DFST-MRD3
  • Vortex Defender-ST 6 MOA Red Dot Sight, Black, 1.8in, 1.48oz, DFST-MRD6 , MPN: DFST-MRD6 , UPC: 843829133302 , Code: VX-RD-VOR0116-DFST-MRD6
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